define("gallery/backbone/0.9.9/backbone-debug", [ "gallery/underscore/1.4.2/underscore-debug", "$-debug" ], function(require, exports) {
    var previousUnderscore = this._;
    var previousJQuery = this.jQuery;
    this._ = require("gallery/underscore/1.4.2/underscore-debug");
    this.jQuery = require("$-debug");
    //     Backbone.js 0.9.9
    //     (c) 2010-2012 Jeremy Ashkenas, DocumentCloud Inc.
    //     Backbone may be freely distributed under the MIT license.
    //     For all details and documentation:
    //     http://backbonejs.org
    (function() {
        // Initial Setup
        // -------------
        // Save a reference to the global object (`window` in the browser, `exports`
        // on the server).
        var root = this;
        // Save the previous value of the `Backbone` variable, so that it can be
        // restored later on, if `noConflict` is used.
        var previousBackbone = root.Backbone;
        // Create a local reference to array methods.
        var array = [];
        var push = array.push;
        var slice = array.slice;
        var splice = array.splice;
        // The top-level namespace. All public Backbone classes and modules will
        // be attached to this. Exported for both CommonJS and the browser.
        var Backbone;
        if (typeof exports !== "undefined") {
            Backbone = exports;
        } else {
            Backbone = root.Backbone = {};
        }
        // Current version of the library. Keep in sync with `package.json`.
        Backbone.VERSION = "0.9.9";
        // Require Underscore, if we're on the server, and it's not already present.
        var _ = root._;
        if (!_ && typeof require !== "undefined") _ = require("gallery/underscore/1.4.2/underscore-debug");
        // For Backbone's purposes, jQuery, Zepto, or Ender owns the `$` variable.
        Backbone.$ = root.jQuery || root.Zepto || root.ender;
        // Runs Backbone.js in *noConflict* mode, returning the `Backbone` variable
        // to its previous owner. Returns a reference to this Backbone object.
        Backbone.noConflict = function() {
            root.Backbone = previousBackbone;
            return this;
        };
        // Turn on `emulateHTTP` to support legacy HTTP servers. Setting this option
        // will fake `"PUT"` and `"DELETE"` requests via the `_method` parameter and
        // set a `X-Http-Method-Override` header.
        Backbone.emulateHTTP = false;
        // Turn on `emulateJSON` to support legacy servers that can't deal with direct
        // `application/json` requests ... will encode the body as
        // `application/x-www-form-urlencoded` instead and will send the model in a
        // form param named `model`.
        Backbone.emulateJSON = false;
        // Backbone.Events
        // ---------------
        // Regular expression used to split event strings.
        var eventSplitter = /\s+/;
        // Implement fancy features of the Events API such as multiple event
        // names `"change blur"` and jQuery-style event maps `{change: action}`
        // in terms of the existing API.
        var eventsApi = function(obj, action, name, rest) {
            if (!name) return true;
            if (typeof name === "object") {
                for (var key in name) {
                    obj[action].apply(obj, [ key, name[key] ].concat(rest));
                }
            } else if (eventSplitter.test(name)) {
                var names = name.split(eventSplitter);
                for (var i = 0, l = names.length; i < l; i++) {
                    obj[action].apply(obj, [ names[i] ].concat(rest));
                }
            } else {
                return true;
            }
        };
        // Optimized internal dispatch function for triggering events. Tries to
        // keep the usual cases speedy (most Backbone events have 3 arguments).
        var triggerEvents = function(obj, events, args) {
            var ev, i = -1, l = events.length;
            switch (args.length) {
              case 0:
                while (++i < l) (ev = events[i]).callback.call(ev.ctx);
                return;

              case 1:
                while (++i < l) (ev = events[i]).callback.call(ev.ctx, args[0]);
                return;

              case 2:
                while (++i < l) (ev = events[i]).callback.call(ev.ctx, args[0], args[1]);
                return;

              case 3:
                while (++i < l) (ev = events[i]).callback.call(ev.ctx, args[0], args[1], args[2]);
                return;

              default:
                while (++i < l) (ev = events[i]).callback.apply(ev.ctx, args);
            }
        };
        // A module that can be mixed in to *any object* in order to provide it with
        // custom events. You may bind with `on` or remove with `off` callback
        // functions to an event; `trigger`-ing an event fires all callbacks in
        // succession.
        //
        //     var object = {};
        //     _.extend(object, Backbone.Events);
        //     object.on('expand', function(){ alert('expanded'); });
        //     object.trigger('expand');
        //
        var Events = Backbone.Events = {
            // Bind one or more space separated events, or an events map,
            // to a `callback` function. Passing `"all"` will bind the callback to
            // all events fired.
            on: function(name, callback, context) {
                if (!(eventsApi(this, "on", name, [ callback, context ]) && callback)) return this;
                this._events || (this._events = {});
                var list = this._events[name] || (this._events[name] = []);
                list.push({
                    callback: callback,
                    context: context,
                    ctx: context || this
                });
                return this;
            },
            // Bind events to only be triggered a single time. After the first time
            // the callback is invoked, it will be removed.
            once: function(name, callback, context) {
                if (!(eventsApi(this, "once", name, [ callback, context ]) && callback)) return this;
                var self = this;
                var once = _.once(function() {
                    self.off(name, once);
                    callback.apply(this, arguments);
                });
                once._callback = callback;
                this.on(name, once, context);
                return this;
            },
            // Remove one or many callbacks. If `context` is null, removes all
            // callbacks with that function. If `callback` is null, removes all
            // callbacks for the event. If `events` is null, removes all bound
            // callbacks for all events.
            off: function(name, callback, context) {
                var list, ev, events, names, i, l, j, k;
                if (!this._events || !eventsApi(this, "off", name, [ callback, context ])) return this;
                if (!name && !callback && !context) {
                    this._events = {};
                    return this;
                }
                names = name ? [ name ] : _.keys(this._events);
                for (i = 0, l = names.length; i < l; i++) {
                    name = names[i];
                    if (list = this._events[name]) {
                        events = [];
                        if (callback || context) {
                            for (j = 0, k = list.length; j < k; j++) {
                                ev = list[j];
                                if (callback && callback !== (ev.callback._callback || ev.callback) || context && context !== ev.context) {
                                    events.push(ev);
                                }
                            }
                        }
                        this._events[name] = events;
                    }
                }
                return this;
            },
            // Trigger one or many events, firing all bound callbacks. Callbacks are
            // passed the same arguments as `trigger` is, apart from the event name
            // (unless you're listening on `"all"`, which will cause your callback to
            // receive the true name of the event as the first argument).
            trigger: function(name) {
                if (!this._events) return this;
                var args = slice.call(arguments, 1);
                if (!eventsApi(this, "trigger", name, args)) return this;
                var events = this._events[name];
                var allEvents = this._events.all;
                if (events) triggerEvents(this, events, args);
                if (allEvents) triggerEvents(this, allEvents, arguments);
                return this;
            },
            // An inversion-of-control version of `on`. Tell *this* object to listen to
            // an event in another object ... keeping track of what it's listening to.
            listenTo: function(object, events, callback) {
                var listeners = this._listeners || (this._listeners = {});
                var id = object._listenerId || (object._listenerId = _.uniqueId("l"));
                listeners[id] = object;
                object.on(events, callback || this, this);
                return this;
            },
            // Tell this object to stop listening to either specific events ... or
            // to every object it's currently listening to.
            stopListening: function(object, events, callback) {
                var listeners = this._listeners;
                if (!listeners) return;
                if (object) {
                    object.off(events, callback, this);
                    if (!events && !callback) delete listeners[object._listenerId];
                } else {
                    for (var id in listeners) {
                        listeners[id].off(null, null, this);
                    }
                    this._listeners = {};
                }
                return this;
            }
        };
        // Aliases for backwards compatibility.
        Events.bind = Events.on;
        Events.unbind = Events.off;
        // Allow the `Backbone` object to serve as a global event bus, for folks who
        // want global "pubsub" in a convenient place.
        _.extend(Backbone, Events);
        // Backbone.Model
        // --------------
        // Create a new model, with defined attributes. A client id (`cid`)
        // is automatically generated and assigned for you.
        var Model = Backbone.Model = function(attributes, options) {
            var defaults;
            var attrs = attributes || {};
            this.cid = _.uniqueId("c");
            this.changed = {};
            this.attributes = {};
            this._changes = [];
            if (options && options.collection) this.collection = options.collection;
            if (options && options.parse) attrs = this.parse(attrs);
            if (defaults = _.result(this, "defaults")) _.defaults(attrs, defaults);
            this.set(attrs, {
                silent: true
            });
            this._currentAttributes = _.clone(this.attributes);
            this._previousAttributes = _.clone(this.attributes);
            this.initialize.apply(this, arguments);
        };
        // Attach all inheritable methods to the Model prototype.
        _.extend(Model.prototype, Events, {
            // A hash of attributes whose current and previous value differ.
            changed: null,
            // The default name for the JSON `id` attribute is `"id"`. MongoDB and
            // CouchDB users may want to set this to `"_id"`.
            idAttribute: "id",
            // Initialize is an empty function by default. Override it with your own
            // initialization logic.
            initialize: function() {},
            // Return a copy of the model's `attributes` object.
            toJSON: function(options) {
                return _.clone(this.attributes);
            },
            // Proxy `Backbone.sync` by default.
            sync: function() {
                return Backbone.sync.apply(this, arguments);
            },
            // Get the value of an attribute.
            get: function(attr) {
                return this.attributes[attr];
            },
            // Get the HTML-escaped value of an attribute.
            escape: function(attr) {
                return _.escape(this.get(attr));
            },
            // Returns `true` if the attribute contains a value that is not null
            // or undefined.
            has: function(attr) {
                return this.get(attr) != null;
            },
            // Set a hash of model attributes on the object, firing `"change"` unless
            // you choose to silence it.
            set: function(key, val, options) {
                var attr, attrs;
                if (key == null) return this;
                // Handle both `"key", value` and `{key: value}` -style arguments.
                if (_.isObject(key)) {
                    attrs = key;
                    options = val;
                } else {
                    (attrs = {})[key] = val;
                }
                // Extract attributes and options.
                var silent = options && options.silent;
                var unset = options && options.unset;
                // Run validation.
                if (!this._validate(attrs, options)) return false;
                // Check for changes of `id`.
                if (this.idAttribute in attrs) this.id = attrs[this.idAttribute];
                var now = this.attributes;
                // For each `set` attribute...
                for (attr in attrs) {
                    val = attrs[attr];
                    // Update or delete the current value, and track the change.
                    unset ? delete now[attr] : now[attr] = val;
                    this._changes.push(attr, val);
                }
                // Signal that the model's state has potentially changed, and we need
                // to recompute the actual changes.
                this._hasComputed = false;
                // Fire the `"change"` events.
                if (!silent) this.change(options);
                return this;
            },
            // Remove an attribute from the model, firing `"change"` unless you choose
            // to silence it. `unset` is a noop if the attribute doesn't exist.
            unset: function(attr, options) {
                return this.set(attr, void 0, _.extend({}, options, {
                    unset: true
                }));
            },
            // Clear all attributes on the model, firing `"change"` unless you choose
            // to silence it.
            clear: function(options) {
                var attrs = {};
                for (var key in this.attributes) attrs[key] = void 0;
                return this.set(attrs, _.extend({}, options, {
                    unset: true
                }));
            },
            // Fetch the model from the server. If the server's representation of the
            // model differs from its current attributes, they will be overriden,
            // triggering a `"change"` event.
            fetch: function(options) {
                options = options ? _.clone(options) : {};
                if (options.parse === void 0) options.parse = true;
                var model = this;
                var success = options.success;
                options.success = function(resp, status, xhr) {
                    if (!model.set(model.parse(resp), options)) return false;
                    if (success) success(model, resp, options);
                };
                return this.sync("read", this, options);
            },
            // Set a hash of model attributes, and sync the model to the server.
            // If the server returns an attributes hash that differs, the model's
            // state will be `set` again.
            save: function(key, val, options) {
                var attrs, current, done;
                // Handle both `"key", value` and `{key: value}` -style arguments.
                if (key == null || _.isObject(key)) {
                    attrs = key;
                    options = val;
                } else if (key != null) {
                    (attrs = {})[key] = val;
                }
                options = options ? _.clone(options) : {};
                // If we're "wait"-ing to set changed attributes, validate early.
                if (options.wait) {
                    if (attrs && !this._validate(attrs, options)) return false;
                    current = _.clone(this.attributes);
                }
                // Regular saves `set` attributes before persisting to the server.
                var silentOptions = _.extend({}, options, {
                    silent: true
                });
                if (attrs && !this.set(attrs, options.wait ? silentOptions : options)) {
                    return false;
                }
                // Do not persist invalid models.
                if (!attrs && !this._validate(null, options)) return false;
                // After a successful server-side save, the client is (optionally)
                // updated with the server-side state.
                var model = this;
                var success = options.success;
                options.success = function(resp, status, xhr) {
                    done = true;
                    var serverAttrs = model.parse(resp);
                    if (options.wait) serverAttrs = _.extend(attrs || {}, serverAttrs);
                    if (!model.set(serverAttrs, options)) return false;
                    if (success) success(model, resp, options);
                };
                // Finish configuring and sending the Ajax request.
                var method = this.isNew() ? "create" : options.patch ? "patch" : "update";
                if (method == "patch") options.attrs = attrs;
                var xhr = this.sync(method, this, options);
                // When using `wait`, reset attributes to original values unless
                // `success` has been called already.
                if (!done && options.wait) {
                    this.clear(silentOptions);
                    this.set(current, silentOptions);
                }
                return xhr;
            },
            // Destroy this model on the server if it was already persisted.
            // Optimistically removes the model from its collection, if it has one.
            // If `wait: true` is passed, waits for the server to respond before removal.
            destroy: function(options) {
                options = options ? _.clone(options) : {};
                var model = this;
                var success = options.success;
                var destroy = function() {
                    model.trigger("destroy", model, model.collection, options);
                };
                options.success = function(resp) {
                    if (options.wait || model.isNew()) destroy();
                    if (success) success(model, resp, options);
                };
                if (this.isNew()) {
                    options.success();
                    return false;
                }
                var xhr = this.sync("delete", this, options);
                if (!options.wait) destroy();
                return xhr;
            },
            // Default URL for the model's representation on the server -- if you're
            // using Backbone's restful methods, override this to change the endpoint
            // that will be called.
            url: function() {
                var base = _.result(this, "urlRoot") || _.result(this.collection, "url") || urlError();
                if (this.isNew()) return base;
                return base + (base.charAt(base.length - 1) === "/" ? "" : "/") + encodeURIComponent(this.id);
            },
            // **parse** converts a response into the hash of attributes to be `set` on
            // the model. The default implementation is just to pass the response along.
            parse: function(resp) {
                return resp;
            },
            // Create a new model with identical attributes to this one.
            clone: function() {
                return new this.constructor(this.attributes);
            },
            // A model is new if it has never been saved to the server, and lacks an id.
            isNew: function() {
                return this.id == null;
            },
            // Call this method to manually fire a `"change"` event for this model and
            // a `"change:attribute"` event for each changed attribute.
            // Calling this will cause all objects observing the model to update.
            change: function(options) {
                var changing = this._changing;
                this._changing = true;
                // Generate the changes to be triggered on the model.
                var triggers = this._computeChanges(true);
                this._pending = !!triggers.length;
                for (var i = triggers.length - 2; i >= 0; i -= 2) {
                    this.trigger("change:" + triggers[i], this, triggers[i + 1], options);
                }
                if (changing) return this;
                // Trigger a `change` while there have been changes.
                while (this._pending) {
                    this._pending = false;
                    this.trigger("change", this, options);
                    this._previousAttributes = _.clone(this.attributes);
                }
                this._changing = false;
                return this;
            },
            // Determine if the model has changed since the last `"change"` event.
            // If you specify an attribute name, determine if that attribute has changed.
            hasChanged: function(attr) {
                if (!this._hasComputed) this._computeChanges();
                if (attr == null) return !_.isEmpty(this.changed);
                return _.has(this.changed, attr);
            },
            // Return an object containing all the attributes that have changed, or
            // false if there are no changed attributes. Useful for determining what
            // parts of a view need to be updated and/or what attributes need to be
            // persisted to the server. Unset attributes will be set to undefined.
            // You can also pass an attributes object to diff against the model,
            // determining if there *would be* a change.
            changedAttributes: function(diff) {
                if (!diff) return this.hasChanged() ? _.clone(this.changed) : false;
                var val, changed = false, old = this._previousAttributes;
                for (var attr in diff) {
                    if (_.isEqual(old[attr], val = diff[attr])) continue;
                    (changed || (changed = {}))[attr] = val;
                }
                return changed;
            },
            // Looking at the built up list of `set` attribute changes, compute how
            // many of the attributes have actually changed. If `loud`, return a
            // boiled-down list of only the real changes.
            _computeChanges: function(loud) {
                this.changed = {};
                var already = {};
                var triggers = [];
                var current = this._currentAttributes;
                var changes = this._changes;
                // Loop through the current queue of potential model changes.
                for (var i = changes.length - 2; i >= 0; i -= 2) {
                    var key = changes[i], val = changes[i + 1];
                    if (already[key]) continue;
                    already[key] = true;
                    // Check if the attribute has been modified since the last change,
                    // and update `this.changed` accordingly. If we're inside of a `change`
                    // call, also add a trigger to the list.
                    if (current[key] !== val) {
                        this.changed[key] = val;
                        if (!loud) continue;
                        triggers.push(key, val);
                        current[key] = val;
                    }
                }
                if (loud) this._changes = [];
                // Signals `this.changed` is current to prevent duplicate calls from `this.hasChanged`.
                this._hasComputed = true;
                return triggers;
            },
            // Get the previous value of an attribute, recorded at the time the last
            // `"change"` event was fired.
            previous: function(attr) {
                if (attr == null || !this._previousAttributes) return null;
                return this._previousAttributes[attr];
            },
            // Get all of the attributes of the model at the time of the previous
            // `"change"` event.
            previousAttributes: function() {
                return _.clone(this._previousAttributes);
            },
            // Run validation against the next complete set of model attributes,
            // returning `true` if all is well. If a specific `error` callback has
            // been passed, call that instead of firing the general `"error"` event.
            _validate: function(attrs, options) {
                if (!this.validate) return true;
                attrs = _.extend({}, this.attributes, attrs);
                var error = this.validate(attrs, options);
                if (!error) return true;
                if (options && options.error) options.error(this, error, options);
                this.trigger("error", this, error, options);
                return false;
            }
        });
        // Backbone.Collection
        // -------------------
        // Provides a standard collection class for our sets of models, ordered
        // or unordered. If a `comparator` is specified, the Collection will maintain
        // its models in sort order, as they're added and removed.
        var Collection = Backbone.Collection = function(models, options) {
            options || (options = {});
            if (options.model) this.model = options.model;
            if (options.comparator !== void 0) this.comparator = options.comparator;
            this._reset();
            this.initialize.apply(this, arguments);
            if (models) this.reset(models, _.extend({
                silent: true
            }, options));
        };
        // Define the Collection's inheritable methods.
        _.extend(Collection.prototype, Events, {
            // The default model for a collection is just a **Backbone.Model**.
            // This should be overridden in most cases.
            model: Model,
            // Initialize is an empty function by default. Override it with your own
            // initialization logic.
            initialize: function() {},
            // The JSON representation of a Collection is an array of the
            // models' attributes.
            toJSON: function(options) {
                return this.map(function(model) {
                    return model.toJSON(options);
                });
            },
            // Proxy `Backbone.sync` by default.
            sync: function() {
                return Backbone.sync.apply(this, arguments);
            },
            // Add a model, or list of models to the set. Pass **silent** to avoid
            // firing the `add` event for every new model.
            add: function(models, options) {
                var i, args, length, model, existing, needsSort;
                var at = options && options.at;
                var sort = (options && options.sort) == null ? true : options.sort;
                models = _.isArray(models) ? models.slice() : [ models ];
                // Turn bare objects into model references, and prevent invalid models
                // from being added.
                for (i = models.length - 1; i >= 0; i--) {
                    if (!(model = this._prepareModel(models[i], options))) {
                        this.trigger("error", this, models[i], options);
                        models.splice(i, 1);
                        continue;
                    }
                    models[i] = model;
                    existing = model.id != null && this._byId[model.id];
                    // If a duplicate is found, prevent it from being added and
                    // optionally merge it into the existing model.
                    if (existing || this._byCid[model.cid]) {
                        if (options && options.merge && existing) {
                            existing.set(model.attributes, options);
                            needsSort = sort;
                        }
                        models.splice(i, 1);
                        continue;
                    }
                    // Listen to added models' events, and index models for lookup by
                    // `id` and by `cid`.
                    model.on("all", this._onModelEvent, this);
                    this._byCid[model.cid] = model;
                    if (model.id != null) this._byId[model.id] = model;
                }
                // See if sorting is needed, update `length` and splice in new models.
                if (models.length) needsSort = sort;
                this.length += models.length;
                args = [ at != null ? at : this.models.length, 0 ];
                push.apply(args, models);
                splice.apply(this.models, args);
                // Sort the collection if appropriate.
                if (needsSort && this.comparator && at == null) this.sort({
                    silent: true
                });
                if (options && options.silent) return this;
                // Trigger `add` events.
                while (model = models.shift()) {
                    model.trigger("add", model, this, options);
                }
                return this;
            },
            // Remove a model, or a list of models from the set. Pass silent to avoid
            // firing the `remove` event for every model removed.
            remove: function(models, options) {
                var i, l, index, model;
                options || (options = {});
                models = _.isArray(models) ? models.slice() : [ models ];
                for (i = 0, l = models.length; i < l; i++) {
                    model = this.get(models[i]);
                    if (!model) continue;
                    delete this._byId[model.id];
                    delete this._byCid[model.cid];
                    index = this.indexOf(model);
                    this.models.splice(index, 1);
                    this.length--;
                    if (!options.silent) {
                        options.index = index;
                        model.trigger("remove", model, this, options);
                    }
                    this._removeReference(model);
                }
                return this;
            },
            // Add a model to the end of the collection.
            push: function(model, options) {
                model = this._prepareModel(model, options);
                this.add(model, _.extend({
                    at: this.length
                }, options));
                return model;
            },
            // Remove a model from the end of the collection.
            pop: function(options) {
                var model = this.at(this.length - 1);
                this.remove(model, options);
                return model;
            },
            // Add a model to the beginning of the collection.
            unshift: function(model, options) {
                model = this._prepareModel(model, options);
                this.add(model, _.extend({
                    at: 0
                }, options));
                return model;
            },
            // Remove a model from the beginning of the collection.
            shift: function(options) {
                var model = this.at(0);
                this.remove(model, options);
                return model;
            },
            // Slice out a sub-array of models from the collection.
            slice: function(begin, end) {
                return this.models.slice(begin, end);
            },
            // Get a model from the set by id.
            get: function(obj) {
                if (obj == null) return void 0;
                return this._byId[obj.id != null ? obj.id : obj] || this._byCid[obj.cid || obj];
            },
            // Get the model at the given index.
            at: function(index) {
                return this.models[index];
            },
            // Return models with matching attributes. Useful for simple cases of `filter`.
            where: function(attrs) {
                if (_.isEmpty(attrs)) return [];
                return this.filter(function(model) {
                    for (var key in attrs) {
                        if (attrs[key] !== model.get(key)) return false;
                    }
                    return true;
                });
            },
            // Force the collection to re-sort itself. You don't need to call this under
            // normal circumstances, as the set will maintain sort order as each item
            // is added.
            sort: function(options) {
                if (!this.comparator) {
                    throw new Error("Cannot sort a set without a comparator");
                }
                if (_.isString(this.comparator) || this.comparator.length === 1) {
                    this.models = this.sortBy(this.comparator, this);
                } else {
                    this.models.sort(_.bind(this.comparator, this));
                }
                if (!options || !options.silent) this.trigger("sort", this, options);
                return this;
            },
            // Pluck an attribute from each model in the collection.
            pluck: function(attr) {
                return _.invoke(this.models, "get", attr);
            },
            // Smartly update a collection with a change set of models, adding,
            // removing, and merging as necessary.
            update: function(models, options) {
                var model, i, l, existing;
                var add = [], remove = [], modelMap = {};
                var idAttr = this.model.prototype.idAttribute;
                options = _.extend({
                    add: true,
                    merge: true,
                    remove: true
                }, options);
                if (options.parse) models = this.parse(models);
                // Allow a single model (or no argument) to be passed.
                if (!_.isArray(models)) models = models ? [ models ] : [];
                // Proxy to `add` for this case, no need to iterate...
                if (options.add && !options.remove) return this.add(models, options);
                // Determine which models to add and merge, and which to remove.
                for (i = 0, l = models.length; i < l; i++) {
                    model = models[i];
                    existing = this.get(model.id || model.cid || model[idAttr]);
                    if (options.remove && existing) modelMap[existing.cid] = true;
                    if (options.add && !existing || options.merge && existing) {
                        add.push(model);
                    }
                }
                if (options.remove) {
                    for (i = 0, l = this.models.length; i < l; i++) {
                        model = this.models[i];
                        if (!modelMap[model.cid]) remove.push(model);
                    }
                }
                // Remove models (if applicable) before we add and merge the rest.
                if (remove.length) this.remove(remove, options);
                if (add.length) this.add(add, options);
                return this;
            },
            // When you have more items than you want to add or remove individually,
            // you can reset the entire set with a new list of models, without firing
            // any `add` or `remove` events. Fires `reset` when finished.
            reset: function(models, options) {
                options || (options = {});
                if (options.parse) models = this.parse(models);
                for (var i = 0, l = this.models.length; i < l; i++) {
                    this._removeReference(this.models[i]);
                }
                options.previousModels = this.models;
                this._reset();
                if (models) this.add(models, _.extend({
                    silent: true
                }, options));
                if (!options.silent) this.trigger("reset", this, options);
                return this;
            },
            // Fetch the default set of models for this collection, resetting the
            // collection when they arrive. If `add: true` is passed, appends the
            // models to the collection instead of resetting.
            fetch: function(options) {
                options = options ? _.clone(options) : {};
                if (options.parse === void 0) options.parse = true;
                var collection = this;
                var success = options.success;
                options.success = function(resp, status, xhr) {
                    var method = options.update ? "update" : "reset";
                    collection[method](resp, options);
                    if (success) success(collection, resp, options);
                };
                return this.sync("read", this, options);
            },
            // Create a new instance of a model in this collection. Add the model to the
            // collection immediately, unless `wait: true` is passed, in which case we
            // wait for the server to agree.
            create: function(model, options) {
                var collection = this;
                options = options ? _.clone(options) : {};
                model = this._prepareModel(model, options);
                if (!model) return false;
                if (!options.wait) collection.add(model, options);
                var success = options.success;
                options.success = function(model, resp, options) {
                    if (options.wait) collection.add(model, options);
                    if (success) success(model, resp, options);
                };
                model.save(null, options);
                return model;
            },
            // **parse** converts a response into a list of models to be added to the
            // collection. The default implementation is just to pass it through.
            parse: function(resp) {
                return resp;
            },
            // Create a new collection with an identical list of models as this one.
            clone: function() {
                return new this.constructor(this.models);
            },
            // Proxy to _'s chain. Can't be proxied the same way the rest of the
            // underscore methods are proxied because it relies on the underscore
            // constructor.
            chain: function() {
                return _(this.models).chain();
            },
            // Reset all internal state. Called when the collection is reset.
            _reset: function() {
                this.length = 0;
                this.models = [];
                this._byId = {};
                this._byCid = {};
            },
            // Prepare a model or hash of attributes to be added to this collection.
            _prepareModel: function(attrs, options) {
                if (attrs instanceof Model) {
                    if (!attrs.collection) attrs.collection = this;
                    return attrs;
                }
                options || (options = {});
                options.collection = this;
                var model = new this.model(attrs, options);
                if (!model._validate(attrs, options)) return false;
                return model;
            },
            // Internal method to remove a model's ties to a collection.
            _removeReference: function(model) {
                if (this === model.collection) delete model.collection;
                model.off("all", this._onModelEvent, this);
            },
            // Internal method called every time a model in the set fires an event.
            // Sets need to update their indexes when models change ids. All other
            // events simply proxy through. "add" and "remove" events that originate
            // in other collections are ignored.
            _onModelEvent: function(event, model, collection, options) {
                if ((event === "add" || event === "remove") && collection !== this) return;
                if (event === "destroy") this.remove(model, options);
                if (model && event === "change:" + model.idAttribute) {
                    delete this._byId[model.previous(model.idAttribute)];
                    if (model.id != null) this._byId[model.id] = model;
                }
                this.trigger.apply(this, arguments);
            }
        });
        // Underscore methods that we want to implement on the Collection.
        var methods = [ "forEach", "each", "map", "collect", "reduce", "foldl", "inject", "reduceRight", "foldr", "find", "detect", "filter", "select", "reject", "every", "all", "some", "any", "include", "contains", "invoke", "max", "min", "sortedIndex", "toArray", "size", "first", "head", "take", "initial", "rest", "tail", "last", "without", "indexOf", "shuffle", "lastIndexOf", "isEmpty" ];
        // Mix in each Underscore method as a proxy to `Collection#models`.
        _.each(methods, function(method) {
            Collection.prototype[method] = function() {
                var args = slice.call(arguments);
                args.unshift(this.models);
                return _[method].apply(_, args);
            };
        });
        // Underscore methods that take a property name as an argument.
        var attributeMethods = [ "groupBy", "countBy", "sortBy" ];
        // Use attributes instead of properties.
        _.each(attributeMethods, function(method) {
            Collection.prototype[method] = function(value, context) {
                var iterator = _.isFunction(value) ? value : function(model) {
                    return model.get(value);
                };
                return _[method](this.models, iterator, context);
            };
        });
        // Backbone.Router
        // ---------------
        // Routers map faux-URLs to actions, and fire events when routes are
        // matched. Creating a new one sets its `routes` hash, if not set statically.
        var Router = Backbone.Router = function(options) {
            options || (options = {});
            if (options.routes) this.routes = options.routes;
            this._bindRoutes();
            this.initialize.apply(this, arguments);
        };
        // Cached regular expressions for matching named param parts and splatted
        // parts of route strings.
        var optionalParam = /\((.*?)\)/g;
        var namedParam = /:\w+/g;
        var splatParam = /\*\w+/g;
        var escapeRegExp = /[\-{}\[\]+?.,\\\^$|#\s]/g;
        // Set up all inheritable **Backbone.Router** properties and methods.
        _.extend(Router.prototype, Events, {
            // Initialize is an empty function by default. Override it with your own
            // initialization logic.
            initialize: function() {},
            // Manually bind a single named route to a callback. For example:
            //
            //     this.route('search/:query/p:num', 'search', function(query, num) {
            //       ...
            //     });
            //
            route: function(route, name, callback) {
                if (!_.isRegExp(route)) route = this._routeToRegExp(route);
                if (!callback) callback = this[name];
                Backbone.history.route(route, _.bind(function(fragment) {
                    var args = this._extractParameters(route, fragment);
                    callback && callback.apply(this, args);
                    this.trigger.apply(this, [ "route:" + name ].concat(args));
                    Backbone.history.trigger("route", this, name, args);
                }, this));
                return this;
            },
            // Simple proxy to `Backbone.history` to save a fragment into the history.
            navigate: function(fragment, options) {
                Backbone.history.navigate(fragment, options);
                return this;
            },
            // Bind all defined routes to `Backbone.history`. We have to reverse the
            // order of the routes here to support behavior where the most general
            // routes can be defined at the bottom of the route map.
            _bindRoutes: function() {
                if (!this.routes) return;
                var route, routes = _.keys(this.routes);
                while ((route = routes.pop()) != null) {
                    this.route(route, this.routes[route]);
                }
            },
            // Convert a route string into a regular expression, suitable for matching
            // against the current location hash.
            _routeToRegExp: function(route) {
                route = route.replace(escapeRegExp, "\\$&").replace(optionalParam, "(?:$1)?").replace(namedParam, "([^/]+)").replace(splatParam, "(.*?)");
                return new RegExp("^" + route + "$");
            },
            // Given a route, and a URL fragment that it matches, return the array of
            // extracted parameters.
            _extractParameters: function(route, fragment) {
                return route.exec(fragment).slice(1);
            }
        });
        // Backbone.History
        // ----------------
        // Handles cross-browser history management, based on URL fragments. If the
        // browser does not support `onhashchange`, falls back to polling.
        var History = Backbone.History = function() {
            this.handlers = [];
            _.bindAll(this, "checkUrl");
            // #1653 - Ensure that `History` can be used outside of the browser.
            if (typeof window !== "undefined") {
                this.location = window.location;
                this.history = window.history;
            }
        };
        // Cached regex for stripping a leading hash/slash and trailing space.
        var routeStripper = /^[#\/]|\s+$/g;
        // Cached regex for stripping leading and trailing slashes.
        var rootStripper = /^\/+|\/+$/g;
        // Cached regex for detecting MSIE.
        var isExplorer = /msie [\w.]+/;
        // Cached regex for removing a trailing slash.
        var trailingSlash = /\/$/;
        // Has the history handling already been started?
        History.started = false;
        // Set up all inheritable **Backbone.History** properties and methods.
        _.extend(History.prototype, Events, {
            // The default interval to poll for hash changes, if necessary, is
            // twenty times a second.
            interval: 50,
            // Gets the true hash value. Cannot use location.hash directly due to bug
            // in Firefox where location.hash will always be decoded.
            getHash: function(window) {
                var match = (window || this).location.href.match(/#(.*)$/);
                return match ? match[1] : "";
            },
            // Get the cross-browser normalized URL fragment, either from the URL,
            // the hash, or the override.
            getFragment: function(fragment, forcePushState) {
                if (fragment == null) {
                    if (this._hasPushState || !this._wantsHashChange || forcePushState) {
                        fragment = this.location.pathname;
                        var root = this.root.replace(trailingSlash, "");
                        if (!fragment.indexOf(root)) fragment = fragment.substr(root.length);
                    } else {
                        fragment = this.getHash();
                    }
                }
                return fragment.replace(routeStripper, "");
            },
            // Start the hash change handling, returning `true` if the current URL matches
            // an existing route, and `false` otherwise.
            start: function(options) {
                if (History.started) throw new Error("Backbone.history has already been started");
                History.started = true;
                // Figure out the initial configuration. Do we need an iframe?
                // Is pushState desired ... is it available?
                this.options = _.extend({}, {
                    root: "/"
                }, this.options, options);
                this.root = this.options.root;
                this._wantsHashChange = this.options.hashChange !== false;
                this._wantsPushState = !!this.options.pushState;
                this._hasPushState = !!(this.options.pushState && this.history && this.history.pushState);
                var fragment = this.getFragment();
                var docMode = document.documentMode;
                var oldIE = isExplorer.exec(navigator.userAgent.toLowerCase()) && (!docMode || docMode <= 7);
                // Normalize root to always include a leading and trailing slash.
                this.root = ("/" + this.root + "/").replace(rootStripper, "/");
                if (oldIE && this._wantsHashChange) {
                    this.iframe = Backbone.$('<iframe src="javascript:0" tabindex="-1" />').hide().appendTo("body")[0].contentWindow;
                    this.navigate(fragment);
                }
                // Depending on whether we're using pushState or hashes, and whether
                // 'onhashchange' is supported, determine how we check the URL state.
                if (this._hasPushState) {
                    Backbone.$(window).bind("popstate", this.checkUrl);
                } else if (this._wantsHashChange && "onhashchange" in window && !oldIE) {
                    Backbone.$(window).bind("hashchange", this.checkUrl);
                } else if (this._wantsHashChange) {
                    this._checkUrlInterval = setInterval(this.checkUrl, this.interval);
                }
                // Determine if we need to change the base url, for a pushState link
                // opened by a non-pushState browser.
                this.fragment = fragment;
                var loc = this.location;
                var atRoot = loc.pathname.replace(/[^\/]$/, "$&/") === this.root;
                // If we've started off with a route from a `pushState`-enabled browser,
                // but we're currently in a browser that doesn't support it...
                if (this._wantsHashChange && this._wantsPushState && !this._hasPushState && !atRoot) {
                    this.fragment = this.getFragment(null, true);
                    this.location.replace(this.root + this.location.search + "#" + this.fragment);
                    // Return immediately as browser will do redirect to new url
                    return true;
                } else if (this._wantsPushState && this._hasPushState && atRoot && loc.hash) {
                    this.fragment = this.getHash().replace(routeStripper, "");
                    this.history.replaceState({}, document.title, this.root + this.fragment + loc.search);
                }
                if (!this.options.silent) return this.loadUrl();
            },
            // Disable Backbone.history, perhaps temporarily. Not useful in a real app,
            // but possibly useful for unit testing Routers.
            stop: function() {
                Backbone.$(window).unbind("popstate", this.checkUrl).unbind("hashchange", this.checkUrl);
                clearInterval(this._checkUrlInterval);
                History.started = false;
            },
            // Add a route to be tested when the fragment changes. Routes added later
            // may override previous routes.
            route: function(route, callback) {
                this.handlers.unshift({
                    route: route,
                    callback: callback
                });
            },
            // Checks the current URL to see if it has changed, and if it has,
            // calls `loadUrl`, normalizing across the hidden iframe.
            checkUrl: function(e) {
                var current = this.getFragment();
                if (current === this.fragment && this.iframe) {
                    current = this.getFragment(this.getHash(this.iframe));
                }
                if (current === this.fragment) return false;
                if (this.iframe) this.navigate(current);
                this.loadUrl() || this.loadUrl(this.getHash());
            },
            // Attempt to load the current URL fragment. If a route succeeds with a
            // match, returns `true`. If no defined routes matches the fragment,
            // returns `false`.
            loadUrl: function(fragmentOverride) {
                var fragment = this.fragment = this.getFragment(fragmentOverride);
                var matched = _.any(this.handlers, function(handler) {
                    if (handler.route.test(fragment)) {
                        handler.callback(fragment);
                        return true;
                    }
                });
                return matched;
            },
            // Save a fragment into the hash history, or replace the URL state if the
            // 'replace' option is passed. You are responsible for properly URL-encoding
            // the fragment in advance.
            //
            // The options object can contain `trigger: true` if you wish to have the
            // route callback be fired (not usually desirable), or `replace: true`, if
            // you wish to modify the current URL without adding an entry to the history.
            navigate: function(fragment, options) {
                if (!History.started) return false;
                if (!options || options === true) options = {
                    trigger: options
                };
                fragment = this.getFragment(fragment || "");
                if (this.fragment === fragment) return;
                this.fragment = fragment;
                var url = this.root + fragment;
                // If pushState is available, we use it to set the fragment as a real URL.
                if (this._hasPushState) {
                    this.history[options.replace ? "replaceState" : "pushState"]({}, document.title, url);
                } else if (this._wantsHashChange) {
                    this._updateHash(this.location, fragment, options.replace);
                    if (this.iframe && fragment !== this.getFragment(this.getHash(this.iframe))) {
                        // Opening and closing the iframe tricks IE7 and earlier to push a
                        // history entry on hash-tag change.  When replace is true, we don't
                        // want this.
                        if (!options.replace) this.iframe.document.open().close();
                        this._updateHash(this.iframe.location, fragment, options.replace);
                    }
                } else {
                    return this.location.assign(url);
                }
                if (options.trigger) this.loadUrl(fragment);
            },
            // Update the hash location, either replacing the current entry, or adding
            // a new one to the browser history.
            _updateHash: function(location, fragment, replace) {
                if (replace) {
                    var href = location.href.replace(/(javascript:|#).*$/, "");
                    location.replace(href + "#" + fragment);
                } else {
                    // #1649 - Some browsers require that `hash` contains a leading #.
                    location.hash = "#" + fragment;
                }
            }
        });
        // Create the default Backbone.history.
        Backbone.history = new History();
        // Backbone.View
        // -------------
        // Creating a Backbone.View creates its initial element outside of the DOM,
        // if an existing element is not provided...
        var View = Backbone.View = function(options) {
            this.cid = _.uniqueId("view");
            this._configure(options || {});
            this._ensureElement();
            this.initialize.apply(this, arguments);
            this.delegateEvents();
        };
        // Cached regex to split keys for `delegate`.
        var delegateEventSplitter = /^(\S+)\s*(.*)$/;
        // List of view options to be merged as properties.
        var viewOptions = [ "model", "collection", "el", "id", "attributes", "className", "tagName", "events" ];
        // Set up all inheritable **Backbone.View** properties and methods.
        _.extend(View.prototype, Events, {
            // The default `tagName` of a View's element is `"div"`.
            tagName: "div",
            // jQuery delegate for element lookup, scoped to DOM elements within the
            // current view. This should be prefered to global lookups where possible.
            $: function(selector) {
                return this.$el.find(selector);
            },
            // Initialize is an empty function by default. Override it with your own
            // initialization logic.
            initialize: function() {},
            // **render** is the core function that your view should override, in order
            // to populate its element (`this.el`), with the appropriate HTML. The
            // convention is for **render** to always return `this`.
            render: function() {
                return this;
            },
            // Remove this view by taking the element out of the DOM, and removing any
            // applicable Backbone.Events listeners.
            remove: function() {
                this.$el.remove();
                this.stopListening();
                return this;
            },
            // For small amounts of DOM Elements, where a full-blown template isn't
            // needed, use **make** to manufacture elements, one at a time.
            //
            //     var el = this.make('li', {'class': 'row'}, this.model.escape('title'));
            //
            make: function(tagName, attributes, content) {
                var el = document.createElement(tagName);
                if (attributes) Backbone.$(el).attr(attributes);
                if (content != null) Backbone.$(el).html(content);
                return el;
            },
            // Change the view's element (`this.el` property), including event
            // re-delegation.
            setElement: function(element, delegate) {
                if (this.$el) this.undelegateEvents();
                this.$el = element instanceof Backbone.$ ? element : Backbone.$(element);
                this.el = this.$el[0];
                if (delegate !== false) this.delegateEvents();
                return this;
            },
            // Set callbacks, where `this.events` is a hash of
            //
            // *{"event selector": "callback"}*
            //
            //     {
            //       'mousedown .title':  'edit',
            //       'click .button':     'save'
            //       'click .open':       function(e) { ... }
            //     }
            //
            // pairs. Callbacks will be bound to the view, with `this` set properly.
            // Uses event delegation for efficiency.
            // Omitting the selector binds the event to `this.el`.
            // This only works for delegate-able events: not `focus`, `blur`, and
            // not `change`, `submit`, and `reset` in Internet Explorer.
            delegateEvents: function(events) {
                if (!(events || (events = _.result(this, "events")))) return;
                this.undelegateEvents();
                for (var key in events) {
                    var method = events[key];
                    if (!_.isFunction(method)) method = this[events[key]];
                    if (!method) throw new Error('Method "' + events[key] + '" does not exist');
                    var match = key.match(delegateEventSplitter);
                    var eventName = match[1], selector = match[2];
                    method = _.bind(method, this);
                    eventName += ".delegateEvents" + this.cid;
                    if (selector === "") {
                        this.$el.bind(eventName, method);
                    } else {
                        this.$el.delegate(selector, eventName, method);
                    }
                }
            },
            // Clears all callbacks previously bound to the view with `delegateEvents`.
            // You usually don't need to use this, but may wish to if you have multiple
            // Backbone views attached to the same DOM element.
            undelegateEvents: function() {
                this.$el.unbind(".delegateEvents" + this.cid);
            },
            // Performs the initial configuration of a View with a set of options.
            // Keys with special meaning *(model, collection, id, className)*, are
            // attached directly to the view.
            _configure: function(options) {
                if (this.options) options = _.extend({}, _.result(this, "options"), options);
                _.extend(this, _.pick(options, viewOptions));
                this.options = options;
            },
            // Ensure that the View has a DOM element to render into.
            // If `this.el` is a string, pass it through `$()`, take the first
            // matching element, and re-assign it to `el`. Otherwise, create
            // an element from the `id`, `className` and `tagName` properties.
            _ensureElement: function() {
                if (!this.el) {
                    var attrs = _.extend({}, _.result(this, "attributes"));
                    if (this.id) attrs.id = _.result(this, "id");
                    if (this.className) attrs["class"] = _.result(this, "className");
                    this.setElement(this.make(_.result(this, "tagName"), attrs), false);
                } else {
                    this.setElement(_.result(this, "el"), false);
                }
            }
        });
        // Backbone.sync
        // -------------
        // Map from CRUD to HTTP for our default `Backbone.sync` implementation.
        var methodMap = {
            create: "POST",
            update: "PUT",
            patch: "PATCH",
            "delete": "DELETE",
            read: "GET"
        };
        // Override this function to change the manner in which Backbone persists
        // models to the server. You will be passed the type of request, and the
        // model in question. By default, makes a RESTful Ajax request
        // to the model's `url()`. Some possible customizations could be:
        //
        // * Use `setTimeout` to batch rapid-fire updates into a single request.
        // * Send up the models as XML instead of JSON.
        // * Persist models via WebSockets instead of Ajax.
        //
        // Turn on `Backbone.emulateHTTP` in order to send `PUT` and `DELETE` requests
        // as `POST`, with a `_method` parameter containing the true HTTP method,
        // as well as all requests with the body as `application/x-www-form-urlencoded`
        // instead of `application/json` with the model in a param named `model`.
        // Useful when interfacing with server-side languages like **PHP** that make
        // it difficult to read the body of `PUT` requests.
        Backbone.sync = function(method, model, options) {
            var type = methodMap[method];
            // Default options, unless specified.
            _.defaults(options || (options = {}), {
                emulateHTTP: Backbone.emulateHTTP,
                emulateJSON: Backbone.emulateJSON
            });
            // Default JSON-request options.
            var params = {
                type: type,
                dataType: "json"
            };
            // Ensure that we have a URL.
            if (!options.url) {
                params.url = _.result(model, "url") || urlError();
            }
            // Ensure that we have the appropriate request data.
            if (options.data == null && model && (method === "create" || method === "update" || method === "patch")) {
                params.contentType = "application/json";
                params.data = JSON.stringify(options.attrs || model.toJSON(options));
            }
            // For older servers, emulate JSON by encoding the request into an HTML-form.
            if (options.emulateJSON) {
                params.contentType = "application/x-www-form-urlencoded";
                params.data = params.data ? {
                    model: params.data
                } : {};
            }
            // For older servers, emulate HTTP by mimicking the HTTP method with `_method`
            // And an `X-HTTP-Method-Override` header.
            if (options.emulateHTTP && (type === "PUT" || type === "DELETE" || type === "PATCH")) {
                params.type = "POST";
                if (options.emulateJSON) params.data._method = type;
                var beforeSend = options.beforeSend;
                options.beforeSend = function(xhr) {
                    xhr.setRequestHeader("X-HTTP-Method-Override", type);
                    if (beforeSend) return beforeSend.apply(this, arguments);
                };
            }
            // Don't process data on a non-GET request.
            if (params.type !== "GET" && !options.emulateJSON) {
                params.processData = false;
            }
            var success = options.success;
            options.success = function(resp, status, xhr) {
                if (success) success(resp, status, xhr);
                model.trigger("sync", model, resp, options);
            };
            var error = options.error;
            options.error = function(xhr, status, thrown) {
                if (error) error(model, xhr, options);
                model.trigger("error", model, xhr, options);
            };
            // Make the request, allowing the user to override any Ajax options.
            var xhr = Backbone.ajax(_.extend(params, options));
            model.trigger("request", model, xhr, options);
            return xhr;
        };
        // Set the default implementation of `Backbone.ajax` to proxy through to `$`.
        Backbone.ajax = function() {
            return Backbone.$.ajax.apply(Backbone.$, arguments);
        };
        // Helpers
        // -------
        // Helper function to correctly set up the prototype chain, for subclasses.
        // Similar to `goog.inherits`, but uses a hash of prototype properties and
        // class properties to be extended.
        var extend = function(protoProps, staticProps) {
            var parent = this;
            var child;
            // The constructor function for the new subclass is either defined by you
            // (the "constructor" property in your `extend` definition), or defaulted
            // by us to simply call the parent's constructor.
            if (protoProps && _.has(protoProps, "constructor")) {
                child = protoProps.constructor;
            } else {
                child = function() {
                    parent.apply(this, arguments);
                };
            }
            // Add static properties to the constructor function, if supplied.
            _.extend(child, parent, staticProps);
            // Set the prototype chain to inherit from `parent`, without calling
            // `parent`'s constructor function.
            var Surrogate = function() {
                this.constructor = child;
            };
            Surrogate.prototype = parent.prototype;
            child.prototype = new Surrogate();
            // Add prototype properties (instance properties) to the subclass,
            // if supplied.
            if (protoProps) _.extend(child.prototype, protoProps);
            // Set a convenience property in case the parent's prototype is needed
            // later.
            child.__super__ = parent.prototype;
            return child;
        };
        // Set up inheritance for the model, collection, router, view and history.
        Model.extend = Collection.extend = Router.extend = View.extend = History.extend = extend;
        // Throw an error when a URL is needed, and none is supplied.
        var urlError = function() {
            throw new Error('A "url" property or function must be specified');
        };
    }).call(this);
    this._ = previousUnderscore;
    this.jQuery = previousJQuery;
});